Resource depletion is a serious problem, but 'footprint' estimates don't tell us much about it 24 July 2019, by Robert B. Richardson
demands on nature exceed what the network's analysts estimate the Earth can regenerate over the entire year. This year they peg the date as July 29—the earliest date since ecological overshoot began in the early 1970s.
As an ecological economist and scholar of sustainability, I am particularly interested in metrics and indicators that can help us understand human uses of Earth's ecosystems. Better measurements of the impacts of human activities can help identify ways to sustain both human well-being and natural resources.
Earth Overshoot Day is a compelling concept and has raised awareness of the growing impact of human activities on the planet. Unfortunately, the methodology used to calculate it and the ecological footprint on which it is based is conceptually flawed Experts widely agree that human activities are and practically unusable in any science or policy harming the global environment. Since the context. In my view, the ecological footprint Industrial Revolution, the world economy has ultimately does not measure overuse of natural grown dramatically. Overall this is a success story, resources—and it may very well underestimate it. since rising incomes have lifted millions of people out of poverty. But it has been fueled by population Rising demands, finite resources growth and increasing consumption of natural resources. The Global Footprint Network estimates when Earth Overshoot Day will arrive based on its Rising demand to meet the needs of more than 7.6 National Footprint Accounts. These include billion people has transformed land use and extensive data sets that the organization uses to generated unprecedented levels of pollution, calculate two overarching indicators: affecting biodiversity, forests, wetlands, water bodies, soils and air quality. The ecological footprint, perhaps the most commonly used metric of the environmental It's pretty certain that humans are consuming more impacts of human resource use. Each country's resources than the Earth can regenerate. An ecological footprint is an estimate of the biological updated estimate of how fast that consumption is resources required to meet its population's happening suggests it's more rapid this year than consumption demands and absorb its carbon in the past 50, according to the California-based emissions. Global Footprint Network. This environmental nonprofit calculates the annual arrival of Earth National biocapacity, which is an estimate of how Overshoot Day – the date when humanity's
1 / 3
well each country's ecosystems can produce the Footprint Network estimates the supply and demand natural resources consumed by humans and of renewable biological resources across six land absorb the waste and pollution that humans use types: forests, fishing grounds, croplands, generate. grazing lands, developed lands and the area of forest required to offset human carbon Both of these measures are expressed in global emissions—that is, the carbon footprint. According to hectares. One hectare is equal to 10,000 square the network's own analysis, each of these land use meters, or about 2.47 acres. types is nearly in balance or in surplus, except for the carbon footprint. Going into overshoot The two key categories for producing To estimate when Earth Overshoot Day will arrive, food—cropland and grazing land—are defined in such the Global Footprint Network calculates the number a way that they can never be in deficit. And the of days in a given year for which Earth has enough analysis does not reflect environmental biocapacity to provide for humans' total ecological consequences of human use of these lands, such footprint. as soil erosion, nutrient runoff or overuse of water. It measures only land area. When the footprint of consumption worldwide exceeds biocapacity, the authors assert that For example, the ecological footprint for Indonesia humans are overshooting, or exceeding the is 1.7 global hectares per person, which is among regenerative capacity of Earth's ecosystems. This the lowest 30% of all countries. But according to a year, they estimate that humans are using natural 2014 study, Indonesia has the highest deforestation resources 1.75 times faster than ecosystems can rate in the world. regenerate—or, put another way, consuming 1.75 Earths. Furthermore, the footprint calculation does not consider whether stocks of natural resources are As an example, the ecological footprint for the decreasing or increasing as a result of human United Kingdom is 4.4 global hectares per person, consumption. This question is critical for and global biocapacity is 1.63 hectares per person. understanding ecological impacts. Therefore, it would take (4.4 /1.63) 2.7 Earths if everyone lived like the British. These national ecological footprint calculations also conflate sustainability with self-sufficiency. They The U.K."s Overshoot Day would be estimated as assume that every nation should produce all of the 365 x (1.63 /4.4) = 135, or the 135th day of the resources it consumes, even though it might be year, which is May 17 based on 2016 data. The less expensive for countries to import some goods United States reached overshoot even earlier, on than to produce them at home. March 15. As an example, the network lists Canada as an What to count? "ecological creditor" whose biocapacity exceeds its population's ecological footprint. However, Canada However, there are some fundamental and is among the top 5 oil-producing countries in the misleading shortcomings in these calculations. In a world, and exports much of that oil for foreign 2013 paper, six authors from academia, The Nature consumption. Most of it goes to the United States, Conservancy and the California-based an "ecological debtor" that consumes more Breakthrough Institute analyzed how the Ecological resources than it produces. Footprint falls short. In their view, it primarily measures humans' carbon footprint but does not Thinking purely in terms of generic "resources," fully address other key impacts. everyone is better off when debtor countries can import resources from nations with supplies to To calculate ecological footprints, the Global spare. There are real and important environmental
2 / 3
impacts associated with producing and consuming oil, but the network's calculations do not address them. Nor do they reflect the decline in natural capital from extracting a nonrenewable resource.
Measuring sustainability
The Global Footprint Network asserts that "You can't manage what you can't measure," but it may be impossible to create a single metric that can capture all human impacts on the environment. Earth Overshoot Day highlights unsustainable uses of natural resources, but we need scientifically robust ecological indicators to inform environmental policy, and a broader understanding of ecological risks.
Better measurements of sustainability should reflect changes in our supplies of natural capital, include estimates of uncertainty and incorporate multiple pathways to reduce carbon footprints. The best tool for measuring human impacts on the planet may be a dashboard of environmental indicators, not a footprint.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Provided by The Conversation APA citation: Resource depletion is a serious problem, but 'footprint' estimates don't tell us much about it (2019, July 24) retrieved 30 September 2021 from https://phys.org/news/2019-07-resource-depletion- problem-footprint-dont.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
3 / 3
Powered by TCPDF (www.tcpdf.org)